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A131415
0
1, 3, 1, 6, 4, 1, 11, 10, 5, 1, 20, 21, 15, 6, 1, 37, 41, 36, 21, 7, 1, 70, 78, 77, 57, 28, 8, 1, 135, 148, 155, 134, 85, 36, 9, 1, 264, 283, 303, 289, 219, 121, 45, 10, 1, 521, 547, 586, 592, 508, 340, 166, 55, 11, 1
OFFSET
0,2
COMMENTS
Left column = A006127: (1, 3, 6, 11, 20, 37,...). Row sums = A047859: (1, 4, 11, 27, 63,...).
FORMULA
(A007318 * A000012) + (A000012 * A007318) - A007318 as infinite lower triangular matrices.
EXAMPLE
First few rows of the triangle are:
1;
3, 1;
6, 4, 1;
11, 10, 5, 1;
20, 21, 15, 6, 1;
37, 41, 36, 21, 7, 1;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jul 08 2007
STATUS
approved